COREC CLINICAL ASSESSMENT The Program Project Grant (PPG) Clinical Assessment Core provides the organizational structure and operations oversight for recruiting normal controls and subjects with Parkinson Disease (PD). Appropriate PD subjects will be referred to the PPG Clinical Assessment Core from four sites: the Movement Disorders Clinics (MvtDCs) in the Department of Neurology at the University of Michigan (DM), the Ann Arbor VA, Medical University of Ohio (MUO), and Michigan State University (MSU). Control subjects will be referred from the Michigan Alzheimer's Disease Center (MADRC) and the UM Claude D. Pepper Older Americans Independence Center (OAIC). Subject-initiated recruitment will be provided via the Michigan Parkinson Foundation and the web-based UM Engage research subject registry. The Clinical Assessment Core will provide central recruiting and standardized assessments for all projects in this PPG. The core will provide an organizational structure and integration for subject characterization with standardized clinical, motor, neurobehavioral/neuropsychiatric, and neuropsychological assessments. The Core will also organize standard imaging for all subjects consisting of brain MRI, and DTBZ and PMP PET imaging. Longitudinal evaluations will be organized for projects 1 and 4. The Core will have diagnostic consensus conferences where cases are discussed and diagnoses assigned;follow-up cases are reviewed for diagnostic reasessment. The Core will also provide the logistic organization for blood sampling for DMA banking (off-site) and assist with brain bank referrals. The PPG Clinical Assessment Core will have a standardized method for data collection, entry and verification and will transfer data to the Tomography and Data Analysis Core (Core B) for analysis.